Software defined satellite network fault detection and migration method and system

Abstract

The invention discloses a software-defined satellite network fault detection and migration method and system. The method comprises the following steps: periodically sending heartbeat packets to a domain controller through a main controller (comprising a ground main controller and a ground backup main controller); the domain controller periodically updates an intra-domain node state and a routing table, and notifies the master controller; and data are periodically synchronized between the ground main controller and the ground backup main controller. When a fault of the ground main controller is detected, the ground backup main controller executes a corresponding migration strategy. And if the domain controller does not receive the heartbeat packet of the main controller in three continuous periods, determining that the main controller is disconnected, and starting a migration strategy. Similarly, if the node in the domain does not receive the heartbeat packet of the domain controller or detects the link fault information in three continuous periods, judging that the domain controller fails, and executing a corresponding migration strategy; the stability and reliability of the satellite network are improved, and the network function can be quickly recovered when a fault occurs.

Description

Technical Field

[0001] The present invention belongs to the technical field of satellite networks and relates to a software-defined satellite network fault detection and migration method and system. Background Art

[0002] With the rapid development of satellite Internet technology, the number of satellites in space-based networks is growing at an unprecedented rate, aiming to provide more timely, detailed and comprehensive services to global users. This trend has not only greatly expanded the coverage of satellite networks, but also significantly improved their service quality and efficiency. However, large-scale constellation networking also brings many technical challenges, especially in satellite control and routing calculation.

[0003] In traditional satellite network architecture, each satellite usually needs to independently handle control functions such as routing decisions, which not only leads to huge consumption of onboard storage and computing resources, but also limits the flexibility and programmability of the network. As the number of satellites continues to increase, this problem becomes more and more prominent, making network control and routing mechanisms based on virtual topology face unprecedented challenges.

[0004] In order to meet this challenge, Software-Defined Networking (SDN) technology came into being and gradually became a feasible research direction for solving satellite network management and control problems. SDN separates control functions such as routing decisions from forwarding devices and transfers them to centralized controllers for unified management, thereby achieving logical centralization of the network control plane and centralized management of resources. This change not only improves the flexibility and programmability of the network, but also makes it possible to integrate heterogeneous network systems.

[0005] In the software-defined satellite network architecture, the control plane and the data plane are completely decoupled. The data plane is mainly composed of low-orbit (LEO) satellites and intersatellite links, and is responsible for the storage and forwarding of data packets. The control plane is responsible for key network functions such as topology management, routing table delivery, network status information collection, as well as basic functions such as global clock synchronization and control message sending and receiving. Through logical centralized control, the control plane can achieve efficient management and control of the entire satellite network and functional updates.

[0006] The typical satellite network architecture consists of a space segment, a ground segment, a control and management segment, and a user segment. The segments work together to achieve functions such as user access, data transmission, network interconnection, system management, and user services. However, the existing satellite network architecture still has many shortcomings when dealing with large-scale constellation networking, such as slow controller failure recovery, insufficient resource utilization, and network flexibility. Summary of the invention

[0007] The purpose of the present invention is to solve the technical problems in the prior art of slow recovery speed, insufficient resource utilization and limited network flexibility of low-orbit satellite networks when a controller fails, and to provide a software-defined satellite network fault detection and migration method and system.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions: A first aspect of the present invention provides a software-defined satellite network fault detection and migration method, comprising the following steps: The main controller and the domain controller both periodically send heartbeat packets; the main controller is a ground main controller or a ground backup main controller; The domain controller periodically updates the node status and routing table within the domain and notifies the master controller; The ground master controller periodically synchronizes its own data with the ground backup master controller; if the ground backup master controller senses a ground master controller failure, it determines that the ground master controller is faulty and implements a corresponding migration strategy for the ground master controller failure; If any domain controller does not receive the heartbeat packet from the master controller within three cycles, it is determined that the master controller is disconnected and the corresponding migration strategy for the master controller disconnection is implemented; If any node in the domain does not receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the heartbeat packet received from the domain controller, the domain controller is determined to be faulty and the migration strategy for the domain controller failure is entered.

[0009] Furthermore, the migration strategy for the ground main controller failure is specifically as follows: The ground backup main controller sends an identity packet to the failed main controller, indicating that it has assumed the function of the main controller; The ground backup main controller takes over the control of the entire network, switches to the main controller, sends identity packets to all domain controllers to announce its own identity, and then periodically broadcasts heartbeat packets; After receiving the identity packet, all domain controllers update the local master controller information and immediately send the intra-domain network status and inter-domain network topology information to the master controller; After the ground main controller recovers from the fault, it switches to the ground backup main controller and periodically synchronizes the main controller information.

[0010] Furthermore, the migration strategy when the main controller loses connection is specifically as follows: If any domain controller detects that it has not received a heartbeat packet from the master controller within three cycles, it will send a disconnection notification to other domain controllers. When any domain controller receives loss of connection notifications from more than half of the domain controllers within three cycles, the domain controller with the least number of satellites in the domain is selected as the on-board temporary master controller; The temporary main controller on the satellite takes over the control of the entire network, sends an identity packet to announce its own identity, and then periodically broadcasts heartbeat packets; After receiving the identity packet, all domain controllers update the local master controller information and immediately send the intra-domain network status and inter-domain network topology information to the onboard temporary master controller; If any domain controller receives a heartbeat packet from the ground for three consecutive cycles, it means that the connection between the domain controller and the main controller has been restored, and the domain controller sends a recovery notification to the temporary main controller on the satellite; When the on-board temporary main controller receives the recovery notification messages from all domain controllers, it returns control to the main controller and synchronizes the management and control data during the loss of connection.

[0011] Furthermore, the migration strategy for the domain controller failure is specifically as follows: If any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, it sends the domain controller failure information to the main controller; The main controller receives the fault information of the domain controller and determines whether the faulty node is a common domain controller or a temporary main controller on the satellite; If the failed node is a common domain controller, the master controller elects a new domain controller and sends the new domain controller information to other domain controller nodes; the new domain controller sends an identity packet to the satellite in the domain to perform the domain controller function; If the failed node is a temporary on-board master controller, the domain controller with the least satellites in the domain is elected as the new temporary on-board master controller.

[0012] Furthermore, the main controller selects a new domain controller using a dynamic re-election algorithm.

[0013] Further, the ground backup main controller senses the failure of the ground main controller, specifically: The ground master controller periodically synchronizes its own data with the ground backup master controller; the self data includes global topology and routing table information; The ground backup main controller did not receive the main controller synchronization data within one cycle, and determined that the ground main controller was completely faulty.

[0014] A second aspect of the present invention provides a software-defined satellite network fault detection and migration method, which is applied to a ground master controller and includes the following steps: Send heartbeat packets periodically; Periodically receive the domain controller's intra-domain node status and intra-domain routing table information; Periodically synchronize its own data to the ground backup main controller; If the data of the ground backup main controller is not synchronized with the ground backup main controller in one cycle, it is judged as a complete failure, and an activation packet is sent to switch the ground backup main controller to the main controller; After the ground main controller recovers from the fault, it switches to the backup main controller and periodically receives its own data from the main controller.

[0015] A third aspect of the present invention provides a software-defined satellite network fault detection and migration method, which is applied to a domain controller and includes the following steps: Send heartbeat packets periodically; Periodically receive heartbeat packets from the master controller and other domain controllers; Periodically send the node status and routing table information within the domain to the main controller; If the heartbeat packet from the master controller is not received within three cycles, a disconnection notification is sent to other domain controllers; If the loss of connection notification is received from more than half of the domain controllers, the domain controller with the least satellites in the domain will be elected as the temporary master controller on the satellite; The onboard temporary master controller sends an identity packet and then periodically broadcasts a heartbeat packet; After receiving the identity packet of the temporary master controller on the satellite, all domain controllers update the local master controller information; When the domain controller receives the heartbeat packet from the master controller for three consecutive cycles, it sends a recovery notification to the temporary master controller on board. When the temporary master controller on board receives the recovery notification messages from all domain controllers, it returns the control to the master controller and synchronizes the control data during the loss of connection. If any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, it sends the domain controller failure information to the main controller; The domain controller receives fault node type information and fault migration information; the fault node type includes an ordinary domain controller or an on-board temporary main controller; the fault migration information includes new domain controller information corresponding to the ordinary domain controller or new on-board temporary main controller information corresponding to the on-board temporary main controller.

[0016] A fourth aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned software-defined satellite network fault detection and migration method is implemented.

[0017] A fifth aspect of the present invention provides a software-defined satellite network fault detection and migration system, comprising: Heartbeat broadcast module, the main controller and the domain controller periodically send heartbeat packets; the main controller is a ground main controller or a ground backup main controller; In the domain information synchronization module, the domain controller periodically updates the node status and routing table in the domain and notifies the main controller; The main control backup module determines that the ground main controller is faulty if the ground backup main controller senses that the ground main controller is faulty, and implements the corresponding migration strategy for the ground main controller fault; The master controller migration module determines that the master controller is disconnected if any domain controller does not receive the heartbeat packet from the master controller within three cycles, and implements the corresponding migration strategy for the master controller disconnection; The domain controller migration module determines that the domain controller is faulty and enters the migration strategy for domain controller failure if any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet from the domain controller.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a software-defined satellite network fault detection and migration method, which realizes real-time monitoring of network status by periodically sending heartbeat packets between the main controller (including the ground main controller and the ground backup main controller) and the domain controller. This mechanism can quickly discover and respond to abnormal conditions in the network, thereby greatly improving the stability and reliability of the entire satellite network. Clear fault detection rules are set, such as the ground backup main controller sensing the ground main controller failure, the domain controller not receiving the main controller heartbeat packet for more than 3 cycles, the node in the domain not receiving the domain controller heartbeat packet or detecting link failure information, etc.; for different types of faults (such as ground main controller failure, main controller loss of connection, domain controller failure, etc.), the method provides corresponding migration strategies. These strategies are intended to minimize the impact of faults on network operation, ensure that network functions can be quickly restored when faults occur, and ensure business continuity; by dynamically updating the node status and routing table in the domain and notifying the main controller, the method enables the satellite network to flexibly adjust the network structure and routing strategy according to the actual operation situation. This adaptability helps to improve the performance and efficiency of the network, and also helps to deal with emergencies in the network. This method reduces the need for manual intervention through automated fault detection and migration mechanisms, thereby reducing operation and maintenance costs. At the same time, since faults can be discovered and handled quickly, long service interruptions and losses caused by faults are avoided.

[0019] Furthermore, in the method of the present invention, when the ground main controller fails, the ground backup main controller can respond quickly, take over the whole network control by sending identity packets, and switch to the main controller role. This process realizes seamless switching, ensures the continuity of network control, and avoids network interruption caused by the failure of the main controller. After switching to the main controller, the ground backup main controller will send identity packets to all domain controllers to notify its own identity, and periodically broadcast heartbeat packets to maintain real-time updates of the network status. After receiving the identity packet, the domain controller will immediately update the local main controller information, and send the network status within the domain and the network topology information between domains to the new main controller, ensuring the accuracy and consistency of the network information. If the ground main controller fails, it can automatically switch back to the ground backup main controller role and periodically synchronize the main controller information. This mechanism ensures a smooth transition after the failure is recovered, avoiding network problems caused by inconsistent main controller status; by implementing the migration strategy of the ground main controller failure, the entire satellite network can maintain a high degree of reliability and stability when facing the main controller failure. This capability is of great significance for ensuring the continuous operation of key services and reducing service interruption time.

[0020] Further, in the method of the present invention, when the main controller loses connection, any domain controller can detect the lack of heartbeat packets and trigger the migration strategy. By sending a loss of connection notification to other domain controllers and collecting feedback, the system can autonomously select a temporary main controller on the satellite to take over the whole network control. This process achieves a rapid response and reduces the network interruption time caused by the loss of connection of the main controller. The domain controller with the least number of satellites in the domain is selected as the temporary main controller on the satellite. This decision is based on the principle of resource optimization. It ensures that the temporary main controller does not over-consume network resources during the takeover process, and can efficiently complete the whole network control task. After the temporary main controller on the satellite takes over, it will send an identity packet to notify its own identity and periodically broadcast heartbeat packets to maintain real-time updates of the network status. After receiving the identity packet, all domain controllers will update the local main controller information and send the network status within the domain and the network topology information between domains to the temporary main controller. This process achieves seamless switching and ensures the accuracy and consistency of network information. When the connection between the main controller and the domain controller is restored, the temporary main controller on the satellite can synchronize the control data during the loss of connection and return the control to the main controller, achieving a smooth transition. The implementation of the migration strategy enables the satellite network to maintain a high degree of robustness in the face of emergencies such as the loss of connection with the main controller. Through distributed decision-making and rapid response mechanisms, the network can quickly restore functions and ensure the continuous operation of key services.

[0021] Further, any node in the domain of the method of the present invention can continuously monitor the heartbeat packet of the domain controller, and when the heartbeat packet is missing or the link fault information is detected, the fault information is sent to the main controller in time. This mechanism ensures the accurate detection of faults and provides a premise for rapid response. After receiving the fault information, the main controller can quickly determine the type of the faulty node and adopt the corresponding migration strategy, thereby effectively reducing the impact of the fault on the network operation. When the ordinary domain controller fails, the main controller can automatically elect a new domain controller to take over its responsibilities. This process realizes seamless switching and ensures the continuity of network control. After taking over, the new domain controller will send an identity packet to the satellite in the domain and perform the domain controller function, thereby maintaining the normal operation of the network. If the temporary main controller on the satellite fails, the main controller can elect the domain controller with the least satellites in the domain as the new temporary main controller on the satellite. This decision is based on the principle of resource optimization, which ensures that the new temporary main controller will not consume excessive network resources during the takeover process. At the same time, due to the automation of the election process, the need for manual intervention is reduced, and the reliability and stability of the network are improved. The implementation of the migration strategy enables the satellite network to maintain a high degree of robustness when facing emergencies such as domain controller failures. Through automatic election and seamless switching mechanisms, the network can quickly restore functions and ensure the continuous operation of key businesses. In addition, this strategy also enhances the network's self-healing ability, allowing the network to self-repair when facing failures, reducing the burden on operation and maintenance personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A diagram of the hierarchical and domain-based multi-controller management and control architecture for software-defined low-orbit satellite networks; Figure 2 A flow chart of the ground main controller failure migration method; Figure 3 The migration method and process of the ground main controller lost contact; Figure 4 The present invention is a block diagram of the software-defined satellite network fault detection and migration method. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and marked in the drawings here can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings: See also Figure 1 , an embodiment of the present invention adopts a hierarchical and domain-based multi-controller management and control architecture for software-defined low-orbit satellite networks to achieve global and efficient control of satellite networks. A ground master controller (Master Controller, MC) and domain controllers (DomainControllers, DC) in multiple satellite domains are deployed in the entire hierarchical and domain-based multi-controller management and control architecture. The ground master controller controls multiple domain controllers by controlling multiple ground stations at the same time. The domain controller is located in the satellite airspace, and one domain controller can communicate with multiple satellites to achieve control of multiple satellites. The hierarchical and domain-based multi-controller management and control architecture reduces the pressure and overhead of a single controller to process multiple nodes at the same time through the hierarchical deployment of multiple domain controllers.

[0028] The ground master controller is the top layer of the hierarchical and domain-based management and control architecture. The ground master controller is located on the ground and has hot backup. The setting of the centralized master controller first takes into account the complexity and dynamics of the satellite network. The use of a single master controller can realize a centralized controller, simplify network management, and avoid overhead such as information synchronization in the distributed control system. Secondly, the centralized master controller has global information of the entire network, which is convenient for understanding the network status and topology, thereby achieving effective coordination and optimization of network resources. Third, a centralized decision-making method is adopted to respond to satellite network emergencies or failures in a timely manner. Fourth, ground deployment allows the use of high-performance servers or dedicated hardware to enhance the ability to handle complex situations and ensure effective network control. Finally, ground deployment simplifies the maintenance and upgrade of the master controller, reduces the energy consumption of the satellite network, and improves reliability.

[0029] Domain controllers form the middle layer of the hierarchical and domain-based management and control architecture. A single domain consists of a domain controller and satellites within the domain. The deployment of domain controllers is highly flexible, facilitating efficient domain management, especially in satellite constellation structures with relatively stable topology. Domain controllers continuously monitor the location, fault status, and network topology of satellites within their domains, and forward this information to the master controller, which uses this data for global optimization and performs tasks such as routing calculations, resource allocation, and monitoring.

[0030] Ordinary satellites form the base layer of the hierarchical and domain-based control architecture, are interconnected through two intra-orbit inter-satellite links and two inter-orbit inter-satellite links, and process data packets according to the commands of the domain controller.

[0031] In order to improve the network performance of the above-mentioned hierarchical and domain-based multi-controller management and control architecture in a fault-frequent scenario and avoid network crashes caused by node or link failures, the present invention provides a software-defined satellite network fault detection and migration method, comprising the following steps: S1, initialize the control architecture: S101, the ground master controller broadcasts an identity packet to announce its own identity; S102, all domain controllers receive the identity packet and save the main controller information; S103, the domain controller collects the initial states of the nodes in the domain and builds a routing table in the domain, and the ground main controller collects the initial states of all satellite nodes and builds a global routing table.

[0032] S2, perform topology discovery and node status update: S201, all domain controllers periodically collect and update the node information, fault node information, and routing table in the domain, and periodically notify the main controller; S202, the ground master controller collects real-time status information of all satellite nodes and periodically updates the global routing table.

[0033] S3, the main controller / domain controller determines the fault type: S301, if the ground backup main controller senses that the ground main controller fails, it enters the migration strategy for the ground main controller failure; S302: If any domain controller in the network does not receive a heartbeat packet sent by the master controller within three cycles, the domain controller determines that the master controller has lost connection, and sends a loss notification to other domain controllers. If any domain controller receives a loss notification from more than half of the domain controllers within three cycles, the migration strategy of the ground master controller being lost is entered; S303: If any node in the domain fails to receive a heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, the domain controller failure information is sent to the main controller, and the migration strategy for the domain controller failure is entered.

[0034] S4: The master controller / domain controller determines the corresponding fault migration strategy based on the fault type: S401, Migration strategy for ground master controller failure: The backup master controller sends an identity packet to the failed master controller, actively takes over the whole network control, and broadcasts the identity packet to all domain controllers to announce its own identity. After receiving the identity packet, all domain controllers immediately send the intra-domain network status and inter-domain network topology information to the new ground master controller. The failed master controller automatically becomes the backup controller after the failure is recovered, and synchronizes the backup data of the master controller.

[0035] like Figure 2 As shown in the figure, the main controller periodically sends heartbeat packets to the domain controller and periodically sends the backup data to the backup controller through the ground network. The ground main controller can sense its own status and actively send an activation packet to the backup main controller when it detects a fault. When the backup controller receives the activation packet from the main controller, it takes over the control of the entire network and broadcasts the identity packet to all domain controllers, announcing that it has become the new main controller. After receiving the identity packet, all domain controllers immediately send the network status within the domain and the inter-domain network topology information to the new ground main controller. The main controller that fails automatically becomes the backup controller after the fault is recovered and synchronizes the backup data of the main controller.

[0036] S402, migration strategy for the loss of connection of the ground master controller: select the domain controller with the least number of satellites in the domain as the temporary master controller on the satellite. All domain controllers continue to receive heartbeat packets from the ground master controller. If the domain controller receives heartbeat packets from the ground master controller within three consecutive cycles, it indicates that the connection between the domain controller and the ground controller has been restored, and a recovery notification is sent to the temporary master controller on the satellite. If the temporary master controller on the satellite receives recovery notification messages from all domain controllers, it will return control to the ground and send network management and control data during the loss of connection to the ground master controller.

[0037] like Figure 3As shown, the main controller periodically sends heartbeat packets to the domain controller. If any domain controller in the network cannot receive the heartbeat packet sent by the main controller within 3 cycles, the domain controller determines that the main controller has lost connection and sends a notification to other domain controllers, indicating that the domain controller has lost connection with the main controller. If any domain controller receives a loss of connection notification from more than half of the domain controllers within 3 cycles, it indicates that the main controller has lost connection, and the domain controller with the least number of satellites in the domain is elected as the temporary main controller on the satellite. All domain controllers continue to receive heartbeat packets from the ground main controller. If the domain controller receives a heartbeat packet from the ground main controller within 3 consecutive cycles, it indicates that the connection between the domain controller and the ground controller has been restored, and a recovery notification is sent to the temporary main controller on the satellite. If the temporary main controller on the satellite receives the recovery notification message from all domain controllers, it returns the main controller to the ground and sends the network control data during the loss of connection to the ground main controller.

[0038] S403, migration strategy for domain controller failure: If the failed domain controller is a normal domain controller, the master controller calls the dynamic re-election algorithm to calculate the new domain controller and sends the new controller ID and other information to other domain controllers in the network. The new domain controller in the domain sends an identity packet to other satellites in the domain to perform the function of the domain controller. If the failed domain controller is a temporary master controller on the satellite, the domain controller with the least number of satellites in the domain is elected as the new temporary master controller on the satellite. All domain controllers continue to receive heartbeat packets from the ground master controller.

[0039] Specifically, if the faulty domain controller is a normal domain controller, a new domain controller is elected according to the dynamic re-election algorithm, and then the domain controller migration is performed. Specifically, the domain controller periodically sends heartbeat packets to all satellites in the domain. If any node in the domain does not receive the heartbeat packet of the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, it sends the domain controller failure information to the main controller. After receiving the failure information of all satellites in the domain, the main controller calls the dynamic re-election algorithm to calculate the new cluster head, designates the new cluster head satellite in the domain as the new domain controller, and sends the new controller ID and other information to other domain controllers in the network. The new domain controller in the domain sends an identity packet to other satellites in the domain to perform the function of the domain controller. At this time, the destination domain controller ID of the heartbeat packet and the identity packet needs to be updated to the new destination domain controller ID. If the faulty domain controller is a temporary master controller on the satellite, that is, the temporary master controller on the satellite fails, similar to the migration method when the ground master controller loses connection, the temporary master controller on the satellite will also periodically send heartbeat packets to the domain controller. If any domain controller in the network cannot receive the heartbeat packet sent by the temporary master controller on the satellite within 3 cycles, the domain controller determines that the temporary master controller on the satellite has lost connection and sends a notification to other domain controllers, indicating that the domain controller has lost connection with the temporary master controller on the satellite. If any domain controller receives a loss of connection notification from more than half of the domain controllers within 1 cycle, it indicates that the temporary master controller on the satellite has failed, and the domain controller with the least number of satellites in the domain is elected as the new temporary master controller on the satellite. All domain controllers continue to receive heartbeat packets from the ground master controller, regardless of the recovery of the temporary master controller on the satellite. The election mechanism for new domain controllers in the domain is consistent with the failure mechanism of ordinary domain controllers.

[0040] The software-defined satellite network fault detection and migration method of the present invention mainly utilizes fault messages to realize fault detection between controllers. The main controller periodically broadcasts heartbeat packets to the domain controllers. If a domain controller fails to receive the heartbeat packet of the main controller after continuous timeout, it enters the fault judgment program and sends inquiry packets to other domain controllers, requiring other domain controllers to return the status of the main controller. The domain controller determines whether the main controller is in a complete failure or disconnected state based on the status information of the returned main controller. If the main controller is in a complete failure state, the main controller is migrated to the ground backup controller; if the main controller is in a disconnected state, the domain controller is elected as the temporary main controller on the satellite. The domain controller and the satellite nodes in the domain will also transmit heartbeat packets. If the domain controller fails, it will migrate to a new domain controller according to the dynamic re-election mechanism.

[0041] The fault message mainly includes heartbeat packets between the main controller and the domain controller, between the domain controller and the nodes in the domain, identity packets and activation packets, etc. The heartbeat packet includes a controller identifier, a destination domain controller ID, a timestamp, a sequence number and status information. The controller identifier is used to uniquely identify the controller that sends the heartbeat packet, which can be the ID of the main controller or the backup main controller. The timestamp is used to record the exact time when the heartbeat packet is sent, which is used to detect delays and confirm the real-time nature of the heartbeat. The sequence number is the serialized number of the heartbeat packet, which is used to track the order of the heartbeat packet to prevent data packets from being lost or repeated. The status information is an optional field, which contains the current status information of the controller, such as CPU usage, memory usage, etc., which helps to monitor the controller status. The identity packet includes a type symbol, a new main controller ID, a destination domain controller ID, a destination controller ID, a timestamp and a validity period. The type symbol clearly identifies that this is an identity packet. The new main controller ID is an ID that uniquely identifies the new main controller. The timestamp is used to record the time when the identity packet is sent to determine the timeliness of the data. The validity period is used to record the valid time window of the identity packet, and the destination domain controller needs to process the identity packet within this time. The activation packet includes a type symbol, a sending domain controller ID, a destination controller ID, a timestamp, and fault information. The type symbol clearly identifies the data packet as an activation packet, and the destination controller ID is the ID of the backup controller that is expected to receive the activation packet. The timestamp is used to record the time when the packet is sent, detect delays, and determine the timeliness of the activation request. The fault information includes relevant information about the detection of a primary controller fault, such as the reception time of the last heartbeat packet.

[0042] In order to reduce the storage overhead of the main controller, the domain controller in the present invention only stores local topology information, the main controller stores global information, and the satellite is invisible to the main controller. The domain controller reports its topological connection status to the main controller. Each satellite node needs to count the performance of the flow, packet loss, etc. of each port in the node, and then encapsulate all interface statistics and data information in the node and send it to the domain controller. After the domain controller constructs the local topology, it periodically notifies the main controller of the local topology.

[0043] When collecting real-time status information of each node in the satellite network, in order to determine the survival status of each node and link, each domain controller needs to periodically check the node status information in the domain. The domain controller notifies the main controller of the fault node information.

[0044] An embodiment of the present invention discloses a software-defined satellite network fault detection and migration system, including: Heartbeat broadcast module, the main controller and the domain controller periodically send heartbeat packets; the main controller is a ground main controller or a ground backup main controller; In the domain information synchronization module, the domain controller periodically updates the node status and routing table in the domain and notifies the main controller; The main control backup module determines that the ground main controller is faulty if the ground backup main controller senses that the ground main controller is faulty, and implements the corresponding migration strategy for the ground main controller fault; The master controller migration module determines that the master controller is disconnected if any domain controller does not receive the heartbeat packet from the master controller within three cycles, and implements the corresponding migration strategy for the master controller disconnection; The domain controller migration module determines that the domain controller is faulty and enters the migration strategy for domain controller failure if any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet from the domain controller.

[0045] An embodiment of the present invention provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a terminal device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the terminal device and extended storage media supported by the terminal device, and can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that more specific examples (non-exhaustive list) of the computer-readable storage medium here include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0046] Computer readable storage media also include data signals propagated in baseband or as part of a carrier wave, which carry readable program codes. Such propagated data signals can take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium can also be any readable medium other than a readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program code contained on the readable storage medium can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0047] Program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0048] The processor may load and execute one or more instructions stored in a computer-readable storage medium to implement the corresponding steps of the software-defined satellite network fault detection and migration method in the above-mentioned embodiment.

[0049] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A software-defined satellite network fault detection and migration method, characterized in that: The following steps are involved: Both the master controller and the domain controller periodically send heartbeat packets; The main controller is a ground main controller or a ground backup main controller; The domain controller periodically updates the node status and routing table within the domain and notifies the master controller; The ground master controller periodically synchronizes its own data with the ground backup master controller; if the ground backup master controller senses a ground master controller failure, it determines that the ground master controller is faulty and implements a corresponding migration strategy for the ground master controller failure; If any domain controller does not receive the heartbeat packet from the master controller within three cycles, it is determined that the master controller is disconnected and the corresponding migration strategy for the master controller disconnection is implemented; If any node in the domain does not receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the heartbeat packet received from the domain controller, the domain controller is determined to be faulty and the migration strategy for the domain controller failure is entered.

2. The software defined satellite network fault detection and migration method according to claim 1, characterized in that: The migration strategy for the ground main controller failure is specifically as follows: The ground backup main controller sends an identity packet to the failed main controller, indicating that it has assumed the function of the main controller; The ground backup main controller takes over the control of the entire network, switches to the main controller, sends identity packets to all domain controllers to announce its own identity, and then periodically broadcasts heartbeat packets; After receiving the identity packet, all domain controllers update the local master controller information and immediately send the intra-domain network status and inter-domain network topology information to the master controller; After the ground main controller recovers from the fault, it switches to the ground backup main controller and periodically synchronizes the main controller information.

3. The software defined satellite network fault detection and migration method according to claim 1, characterized in that: The migration strategy when the main controller loses connection is specifically as follows: If any domain controller detects that it has not received a heartbeat packet from the master controller within three cycles, it will send a disconnection notification to other domain controllers. When any domain controller receives loss of connection notifications from more than half of the domain controllers within three cycles, the domain controller with the least number of satellites in the domain is selected as the on-board temporary master controller; The temporary main controller on the satellite takes over the control of the entire network, sends an identity packet to announce its own identity, and then periodically broadcasts heartbeat packets; After receiving the identity packet, all domain controllers update the local master controller information and immediately send the intra-domain network status and inter-domain network topology information to the onboard temporary master controller; If any domain controller receives a heartbeat packet from the ground for three consecutive cycles, it means that the connection between the domain controller and the main controller has been restored, and the domain controller sends a recovery notification to the temporary main controller on the satellite; When the on-board temporary main controller receives the recovery notification messages from all domain controllers, it returns control to the main controller and synchronizes the management and control data during the loss of connection.

4. The software defined satellite network fault detection and migration method according to claim 1, characterized in that: The migration strategy for the domain controller failure is specifically as follows: If any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, it sends the domain controller failure information to the main controller; The main controller receives the fault information of the domain controller and determines whether the faulty node is a common domain controller or a temporary main controller on the satellite; If the failed node is a common domain controller, the master controller elects a new domain controller and sends the new domain controller information to other domain controller nodes; the new domain controller sends an identity packet to the satellite in the domain to perform the domain controller function; If the failed node is a temporary on-board master controller, the domain controller with the least satellites in the domain is elected as the new temporary on-board master controller.

5. The software defined satellite network fault detection and migration method according to claim 4, characterized in that: The master controller elects a new domain controller using a dynamic re-election algorithm.

6. The software defined satellite network fault detection and migration method according to claim 1, characterized in that: The ground backup main controller senses a ground main controller failure, specifically: The ground master controller periodically synchronizes its own data with the ground backup master controller; the self data includes global topology and routing table information; The ground backup main controller did not receive the main controller synchronization data within one cycle, and determined that the ground main controller was completely faulty.

7. A software-defined satellite network fault detection and migration method, applied to a ground master controller, characterized in that: The following steps are involved: Send heartbeat packets periodically; Periodically receive the domain controller's intra-domain node status and intra-domain routing table information; Periodically synchronize its own data to the ground backup main controller; If the data of the ground backup main controller is not synchronized with the ground backup main controller in one cycle, it is judged as a complete failure, and an activation packet is sent to switch the ground backup main controller to the main controller; After the ground main controller recovers from the fault, it switches to the backup main controller and periodically receives its own data from the main controller.

8. A software-defined satellite network fault detection and migration method, applied to a domain controller, characterized in that: The following steps are involved: Send heartbeat packets periodically; Periodically receive heartbeat packets from the master controller and other domain controllers; Periodically send the node status and routing table information within the domain to the main controller; If the heartbeat packet from the master controller is not received within three cycles, a disconnection notification is sent to other domain controllers; If the loss of connection notification is received from more than half of the domain controllers, the domain controller with the least satellites in the domain will be elected as the temporary master controller on the satellite; The onboard temporary master controller sends an identity packet and then periodically broadcasts a heartbeat packet; After receiving the identity packet of the temporary master controller on the satellite, all domain controllers update the local master controller information; When the domain controller receives the heartbeat packet from the master controller for three consecutive cycles, it sends a recovery notification to the temporary master controller on board. When the temporary master controller on board receives the recovery notification messages from all domain controllers, it returns the control to the master controller and synchronizes the control data during the loss of connection. If any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet, it sends the domain controller failure information to the main controller; The domain controller receives the fault node type information and fault migration information; The fault node type includes a common domain controller or an on-board temporary master controller; the fault migration information includes new domain controller information corresponding to the common domain controller or new on-board temporary master controller information corresponding to the on-board temporary master controller.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the software-defined satellite network fault detection and migration method according to any one of claims 1 to 8 is implemented.

10. A software-defined satellite network fault detection and migration system, characterized in that: include: Heartbeat broadcast module, the main controller and domain controller periodically send heartbeat packets; The main controller is a ground main controller or a ground backup main controller; In the domain information synchronization module, the domain controller periodically updates the node status and routing table in the domain and notifies the main controller; The main control backup module determines that the ground main controller is faulty if the ground backup main controller senses that the ground main controller is faulty, and implements the corresponding migration strategy for the ground main controller fault; The master controller migration module determines that the master controller is disconnected if any domain controller does not receive the heartbeat packet from the master controller within three cycles, and implements the corresponding migration strategy for the master controller disconnection; The domain controller migration module determines that the domain controller is faulty and enters the migration strategy for domain controller failure if any node in the domain fails to receive the heartbeat packet from the domain controller for three consecutive cycles, or detects link failure information in the received heartbeat packet from the domain controller.

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